As implantable medical device (IMD) technology advances in an attempt to address a myriad of life sustaining/enhancing needs, issues such as IMD battery longevity, IMD size and shape, IMD mass, and patient comfort remain key considerations in the IMD design process. Much attention is typically placed on the power source of an implantable medical device during the IMD design process. Battery size and capacity, for example, significantly impact the physical configuration of the IMD and the duration of service time within the patient before battery replacement or recharge is required.
A conventional approach to providing power within an implantable medical device involves the use of a self-contained battery, not unlike a common battery which is commercially available to the consumer. Such a self-contained battery includes active electrochemical cell components housed in a battery can. Battery housing connectors or contacts are provided for establishing electrical connections to circuitry disposed within the implantable medical device.
The battery component of an IMD requires the allocation of an appreciable percentage of usable space within the IMD. For this reason, reducing the size of an IMD battery is a desirable design objective. However, reducing IMD battery size results in a corresponding reduction in battery capacity, which necessarily places limits on the ability to make significant battery size reductions using conventional IMD battery design principles.
Moreover, the can of a conventional IMD battery may create “dead space” within the implantable medical device (e.g., a can having a substantially square or rectangular shape). Although a thoughtful design approach can help to reduce the amount of such dead space, an appreciable volume of space within the IMD typically remains unusable when employing a conventional IMD battery.